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    <title>ShellCheck: SC2239 – Ensure the shebang uses the absolute path to the interpreter.</title>
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    <h1>SC2239 – ShellCheck Wiki</h1>
    <a href="https://github.com/koalaman/shellcheck/wiki/SC2239">See this page on GitHub</a>
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    <h2
id="ensure-the-shebang-uses-the-absolute-path-to-the-interpreter">Ensure
the shebang uses the absolute path to the interpreter.</h2>
<h3 id="problematic-code">Problematic code:</h3>
<div class="sourceCode" id="cb1"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb1-1"><a href="SC2239.html#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="co">#!bin/sh</span></span>
<span id="cb1-2"><a href="SC2239.html#cb1-2" aria-hidden="true" tabindex="-1"></a><span class="bu">echo</span> <span class="st">&quot;Hello World&quot;</span></span></code></pre></div>
<h3 id="correct-code">Correct code:</h3>
<div class="sourceCode" id="cb2"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb2-1"><a href="SC2239.html#cb2-1" aria-hidden="true" tabindex="-1"></a><span class="co">#!/bin/sh</span></span>
<span id="cb2-2"><a href="SC2239.html#cb2-2" aria-hidden="true" tabindex="-1"></a><span class="bu">echo</span> <span class="st">&quot;Hello World&quot;</span></span></code></pre></div>
<h3 id="rationale">Rationale:</h3>
<p>The script's interpreter, as specified in the shebang, does not start
with a <code>/</code>.</p>
<p>The interpreter should always be specified by absolute path to ensure
that the script can be executed from any directory. When it's not, it's
generally a typo like in the problematic example.</p>
<p>If you don't know where the interpreter is and you hoped to use
<code>#! bash</code>, this is not an option. Use
<code>/usr/bin/env</code> instead:</p>
<div class="sourceCode" id="cb3"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb3-1"><a href="SC2239.html#cb3-1" aria-hidden="true" tabindex="-1"></a><span class="co">#!/usr/bin/env bash</span></span>
<span id="cb3-2"><a href="SC2239.html#cb3-2" aria-hidden="true" tabindex="-1"></a><span class="bu">echo</span> <span class="st">&quot;Hello World&quot;</span></span></code></pre></div>
<p>While not required by POSIX, <code>env</code> can essentially always
be found in <code>/usr/bin</code> and will search the PATH for the
specified executable.</p>
<h3 id="exceptions">Exceptions:</h3>
<p>None.</p>
<h3 id="related-resources">Related resources:</h3>
<ul>
<li>Help by adding links to BashFAQ, StackOverflow, man pages, POSIX,
etc!</li>
</ul>
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    <p style='font-size: 80%'><a href="../index.html">ShellCheck</a> is a static analysis tool for shell scripts. This page is part of its documentation.</p>
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